A Florida-based firm advertising cheap, Mac-compatible systems running on standardised hardware has created a swirl of controversy this week — and drawn an angry response from one of the principal hackers involved in developing the software involved.

Aside from the legal ramifications of selling "white-box" systems running Apple's Mac OS X, questions have arisen over the exact nature of Psystar, the firm advertising the systems; and even whether it exists.

As of Thursday afternoon, Psystar appears to be a small operation that has only recently established a web presence, and which is struggling to cope with the sudden interest aroused by its Mac clone. The product's name has changed over the past week, from Open Mac to Open Computer. Moreover, the company's postal address has changed several times over the past week.

In various published reports, Psystar has explained this is due to a genuine change of address followed by one or several typographical errors on the website's "contact" page.

Psystar's e-commerce site has suffered outages, and while it is currently functioning, users have noticed some anomalies — at one point, for instance, the site required users to submit a credit-card number, but then would accept only PayPal payments.

The Open Computer's basic model, at $399 (£200), is advertised as featuring a 2.2GHz Intel Core 2 Duo CPU, 2GB of DDR 2 memory, a 250GB hard disk drive, multi-format DVD writer and integrated graphics. Buying a copy of Leopard adds $150 to the price. This compares to $599 for the Mac Mini, Apple's lowest-cost model, which features less powerful hardware.

Apple allowed a handful of companies to manufacture Mac clones in the mid-1990s, but Steve Jobs put an end to the practice when he resumed his chief executive duties in 1997.

Psystar claims to be mainly a regional IT support company, which has focused on VoIP integration for "several years" and which added the Open Computer to its offerings last month.

The company's principal, as confirmed by state records, is Rudy Pedraza, whom records show as having been involved in a series of businesses over the years, including a lift company and an IT support firm called Floridatek.

As yet, no users appear to have reported receiving an Open Computer. The first shipments are due to begin in seven to 10 days, Psystar representatives have said, according to reports.

OSx86 angerIf the Open Computer does in fact exist, Apple might not be too happy about it — but neither will the hackers who have developed the "OSx86" software Psystar claims to use. Thus far, Apple has made no concerted effort to stamp out the OSx86 project, which consists of various patches allowing Mac OSX to run on commodity hardware, no doubt in part because it has been used only on a small scale and is relatively difficult to implement.

Psystar is proposing, however, to use OSx86-developed tools as the basis for its systems. On its website, the firm specifically mentions PC EFI V8, an emulator for the Extensible Firmware Interface (EFI) that lies between OSX and the Intel firmware.

Netkas, the programmer who led the PC EFI effort, retorted angrily to Psystar on his blog. "This is a violation of my authorship rights on PC EFI V8," he wrote. The patch's licence forbids any "redistribution... for direct or indirect commercial purposes", Netkas wrote.

Following complaints from OSx86 hackers, Psystar added a statement to its website crediting Netkas for the PC EFI software. "To the open-source community: thank you," the statement said.

The installation of OSX on a non-Apple computer is expressly forbidden by Apple's end-user licensing agreement (EULA). Nevertheless, some lawyers have said Apple will have a hard time stopping firms such as Psystar from breaking the agreement, because of the relative weakness of breach-of-contract disputes.

Apple was contacted for comment but did not respond in time for this article.